1. Field of the Invention
The invention relates to a method of producing a synthetic lyophobic layer and somewhat more particularly to a method of producing a lyophobic layer on surfaces of a jet-orifice carrier of a recording device functioning with liquid droplets.
2. Prior Art
Recording devices functioning by controllably ejecting liquid droplets through a jet-orifice are known, for example, from German OS No. 25 27 647. In this type of device, at least one jet-orifice is provided in a carrier for recording indicia with a writing fluid being ejected from the jet-orifice as needed and being applied to a recording medium disposed in front of the discharge opening of the jet-orifice.
In order to prevent a surface of the jet-orifice carrier facing a recording media from being moistened by oozing writing fluid and thereby producing recorded artifacts which disrupt print quality, this carrier surface can be provided with a layer of material which exhibits a surface tension lower than that of the writing fluids. These lyophobic, i.e. liquid-repelling, layers can be composed of synthetic materials such as polyethylene or, preferably, polytetrafluoroethylene.
As is known, polytetrafluoroethylene layers can be produced by sintering a powder or dispersion of particulate polytetrafluoroethylene raw material. However, it is difficult to control the coating thickness of layers produced in this manner. Further, the coated surfaces become slightly granular and partial coverage of surfaces defining the jet-orifice is difficult to avoid.